1. Field of the Present Invention
The present invention relates to high-frequency signal lines and electronic devices including the high-frequency signal lines, and more particularly relates to a high-frequency signal line including a signal conductive layer and a ground conductive layer, and an electronic device including the high-frequency signal line.
2. Description of the Related Art
A signal line described in, for example, Japanese Unexamined Patent Application Publication No. 2011-71403 is known as a high-frequency signal line of related art. FIGS. 20A to 20D provide an exploded view of a signal line 500 described in Japanese Unexamined Patent Application Publication No. 2011-71403.
The signal line 500 includes insulating sheets 522a to 522d, ground conductors 530 and 534, and a signal line portion 532. The insulating sheets 522a to 522d are stacked in that order from the upper side to the lower side. The ground conductors 530 and 534 are provided on the insulating sheets 522b and 522d, respectively. The signal line portion 532 is provided on the insulating sheet 522c. Hence, the signal line portion 532 is sandwiched between the insulating sheets 522b and 522d in the vertical direction. With the signal line 500 configured as described above, the thickness can be decreased as compared with a typical coaxial cable. Accordingly, the signal line 500 can be arranged in a small gap in a casing of a high-frequency device, such as a mobile communication terminal.
However, with the signal line 500 described in Japanese Unexamined Patent Application Publication No. 2011-71403, it may be difficult to bend the signal line 500 for use. To be more specific, in the signal line 500, since the ground conductors 530 and 534 and the signal line portion 532 are made of metal, such as copper, these parts are less likely deformed as compared with the insulating sheets 522a to 522d made of polyimide. Hence, if the ground conductors 530 and 534 and the signal line portion 532 overlap each other in the stacking direction like the signal line 500, it may be difficult to bend the signal line 500.